Saturday, February 25, 2012

Beyond Net Zero?

Now that a run-of-the-mill homebuilder can offer a net zero energy cost home, you might consider going beyond net zero.  Your house could generate more energy than it uses, and actually put money in your pocket.

How much could you make?  Well, according to these rules,  you can't install more than 20% excess solar capacity, and they will only pay you wholesale prices for it:

Net Metering shall be, for billing purposes, the net
consumption as measured at the Company’s service meter.
However, in the event net metering is negative such that the
Eligible Energy Resource’s production is greater than the
Customer’s consumption in any month, the Company will not
credit Customer for such negative consumption. The negative
consumption shall be considered as energy available to offset
consumption in subsequent months. However, in the event that
such negative consumption balance remains at the end of a
calendar year, Company will pay Customer for such negative
consumption balance at the rate that reflects the Company’s
average hourly incremental cost of electricity supply over the
most recent calendar year. Payment shall be made within sixty
(60) days of the end of each calendar year, or within sixty
(60) days of when the customer terminates its retail service.
Customer may make a one-time election, in writing, to have the
Company carry forward the Customer’s negative consumption as a
credit from month to month indefinitely until the customer
terminates service, at which time no payment shall be made by
the Company for any remaining negative consumption balance.

For new construction, you could make a high guess at your consumption, and maybe get away with more that the 120% limit.

Wednesday, February 1, 2012

Simplest Split Solar System Ever?

As you may know, I was originally trained as a Solar Engineer (solar water and air heating).  In the early 80's, we learned a lot of things on our own because:

1.  Manufacturers supplied only components, not complete systems.

2.  Because every house is different, every installation is unique, causing mistakes and "issues".

In my opinion, the solar water heating industry has still not  matured.  Because systems currently cost too much, they aren't being installed as often as they should (which is on every house in the Denver area).  For high volume uptake to occur, NREL says the installed price needs to be between $1,000 and $3,000, not the $6,000-$11,000 that you typically find.

Recently, I've been back to learning things on my own, and collaborating with folks like genius Steve Baer.
Some of us have been working on solar system simplification.  One simple domestic hot water system that  has tested successfully is depicted in the video on YouTube below.   If your house has the right configuration, I can install this system for you for $1850-$2600 with a 5 year warranty.  It may be simple, but it requires some high tech to succeed.  The collector we must use has the lowest heat loss coefficient of any mass marketed panel.